Alkenyl and Related Compounds

6 Alkenyl and related compounds. The crystal structure of (CH2=CHU.THF)4 has been determined in THF solution, a tetrama-dimer equilibrium is established. Lithium-hydrogen distances in solution were derived from Li- H HOESY ejqwriments. The unsolvated virtyl- 

Theoraical studies have been carried out on (a) Li2C=CLi2 (at the MP2/6-316 levd), (b) (CH2=CHCH2Li)2 (MNDO calculation),(c) pentadienyl-lithium (MNDO study) and (d) MeCH= H H2,M+ (13 M=Li, Na, K or Rb) ab initio calculation uang diffuse function augmented split valence basis sets) c -geometries ae favoured for (13). 

Hexadienyl-caesium compounds have been generated from 1,4-, 2,4- or 1,5-hexadienes with Cs/18-crown-6 or BuLi/Bu OCs in THE the geometries in solution were deduced from the derivatisation products.  

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